1. Field of the Invention
The present invention relates to a medicament for animals directed to cats, more particularly to a therapeutic agent for cat respiratory diseases which contains a human interferon(s) (sometimes abbreviated as "HuIFN(s)" hereinafter) as an effective ingredient.
2. Description of the Prior Art
Recently, the number of people, who find their daily lives enriched by their pet animals has been increasing as their incomes and life-styles improve. Among pet animals, especially cats and dogs have been the most popular from antiquity, and a variety of species of these animals have been produced by successive breedings for many years. Some of these species are amazingly costly. As is evident from the above-mentioned recent tendency, the number of tame cats has been remarkably increasing, and this results in an increase of cats being brought to veterinary hospitals.
Excluding cats with traumas and fractures requiring surgery, the number of other cats suffering from infectious diseases, especially respiratory diseases, i.e. "feline cold", and being brought to veterinary hospitals, is increasing. The main inducer of feline cold has been deemed to be viruses which infect feline airways, and felines infected with viruses mostly show common cold-like symptoms such as cough, rhinorrhea, drooling, fever, inflammation of superior airway, pneumonia, stomatitis, glossitis, conjunctivitis, granular adenitis, lingual ulcer, ulcer of nasal end, systematic skin ulcer, turbinal ulcer, scours, vomiting, anorexia and reduction of vitality. More particularly, when felines are infected with feline immunodeficiency virus (sometimes abbreviated as "FIV" hereinafter), they become more likely to show the above-mentioned symptoms and rapidly weaken. At present, there exists no treatment worth mentioning for feline virus diseases as well as feline respiratory diseases, and actually these diseases are only treated with symptomatic treatments such as trophotherapy by administering to felines to be treated nutrient feeds in order to relieve their dehydration symptoms and to recover their physical vitality, as well as administering antibiotics to them to prevent multiple or secondary infections, and physically removing viscous secreta.
Recently, it was reported by Tomiya UCHINO et al., in Shodobutsu-Rinsho, Vol.11, No.6, pp.11-25 (1992) that an intravenous administration of several millions of international units of a recombinant feline interferon to a feline suffering from respiratory diseases exerted a considerably-high therapeutic effect. In order to attain the desired effect, the administration, however, requires a very large amount of feline interferon, and this subjects their owners to an excessive economical burden: The increment of the owners's economical burden is unavoidable because biologically active polypeptides such as interferons, even though they are recombinant types, are generally too expensive, and because successive administrations of such interferons further increases their economical burden. In general, cats requires very careful handling because of their nervousness and great wariness, so that other administrations, excluding intravenous administration, which attain a satisfactory efficacy, are favorably employed by veterinarians who actually treat cats.
Thus, the development of methods to more loosely treat cat respiratory diseases with satisfactorily-high efficacy, as well as to reduce the financial burden their owners has been in great demand.